The investigative team at WCVB TV in Boston ran a story yesterday about an unknown substance in fluoride imported from China. Team 5 Investigates found the Amesbury Water Department pulled fluoride from its system amid concerns about its supply from China, the news station reported. Department of Public Works Director Rob Desmarais said after he mixes the white powder with water, 40 percent of it will not dissolve. Desmarais said the residue clogs his machines and makes it difficult to get a consistent level of fluoride in the towns water.distracts-from-fact-fluoride-is-a-deadly­-killer/